Skeptical SCOTUS in environmental case

From NBC's Pete WilliamsSix states, New York City, and three conservation groups ran into a buzz saw at the U.S. Supreme Court today, likely signaling an end to their legal battle against five big power companies over global warming.

The Supreme Court Building is seen last month on Capitol Hill in Washington. (AP)

They filed their lawsuit in 2004, hoping to have a legal fallback ready in the event the Environmental Protection Agency chooses not to impose carbon dioxide pollution limits on existing power plants. The states, New York, and the conservation groups -- collectively, the plaintiffs -- claimed that those power plants were creating a public nuisance, releasing greenhouse gasses that contribute to global warming and cause environmental damage. The power plants they targeted, their suit said, emit ten percent of the entire country's carbon dioxide pollution.

But based on comments from the justices during today's oral argument, it's doubtful the plaintiffs have a single vote on the court in favor of keeping their lawsuit going. Chief Justice John Roberts noted that the EPA has decided to look at whether CO2 emissions from existing plants should be regulated. "Doesn't that mean that this federal action displaces any right to sue under common law?" he asked.

Even the court's more liberal justices hinted that they doubted the plaintiffs could keep their public nuisance suit going. "The relief you seek sounds like what the EPA does. You want to turn federal judges into a super-EPA," said Justice Ruth Bader Ginsburg.

The justices were also skeptical that the plaintiffs could successfully attribute a measurable change in global warming -- a worldwide phenomenon -- to a single group of polluters. The states claim they can do so based on past cases in which one state sues a company in another state for causing pollution that creates a public nuisance. "But there's a huge gap or chasm between state pollution cases and this global one," said Justice Elena Kagan.

The EPA has said it will decide by May of 2012 whether to regular CO2 emissions from existing plants. Environmental groups wanted this lawsuit to be a fallback in the event it views the EPA's action as insufficient. But it now seems doubtful that legal safety net will be available.